Goodwill and Intangible Assets (Reconciliation of Intangible Assets) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019	Jul. 31, 2019
Finite-Lived Intangible Assets
Gross Carrying Amount	$ 124.2		$ 124.2		$ 123.8
Accumulated Amortization	(58.9)		(58.9)		(52.9)
Total	65.3		65.3		70.9
Amortization expense	2.1	$ 2.1	6.4	$ 5.6
Customer relationships
Finite-Lived Intangible Assets
Gross Carrying Amount	101.8		101.8		101.5
Accumulated Amortization	(47.9)		(47.9)		(43.3)
Total	53.9		53.9		58.2
Patents, trademarks and technology
Finite-Lived Intangible Assets
Gross Carrying Amount	22.4		22.4		22.3
Accumulated Amortization	(11.0)		(11.0)		(9.6)
Total	$ 11.4		$ 11.4		$ 12.7

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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